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what is the dimensional formula of epcilon

The value of ?₀ is defined by the formula

where c is the defined value for the speed of light in classical vacuum in SI units,and ?₀ is the parameter that international Standards Organizations call the "magnetic constant" (commonly called vacuum permeability). Since ?₀ has the defined value 4? × 10^?7 H m^?1, and c has the defined value 299792458 m·s^?1, it follows that ?₀ has a defined value given approximately by

?₀ ? 8.854187817620... × 10^?12 F·m^?1 (or A²·s⁴·kg^?1·m^?3 in SI base units, or C²·N^?1·m^?2 or C·V^?1·m^?1 using other SI coherent units).

So the dimension is [M^-1L^-3T²Q²] or in terms of current, [M^-1L^-3T⁴I² ] where I represents current.